Electromagnetic relay



P, H.A ESTES 2,391 ,'692

ELECTROMAGNETIC RELAY Filed July 25, 1942 Inventor# /Z /0 Phillip Estes Pirenei Deze', 19e@ y l 2,391,692l

' UNITED s `STATES PATENT OFFICE ELECTROMAGNETIC RELAY Phillip H.Estes, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application July'25, 1942, Serial No. 452,295

Claims. (Cl. 175-336) My invention relates ingeneral to electromagtively large transient or persistent, oscillatory or netic relays and more particularly to relays unidirectional accelerating forces. n specially designed to evidence a high degree of It is a still further object of my invention to humidity. subiection to relatively large vibratory impact or The 'invention is particularly useful in connecother accelerating forces.

tion with vehicles or other mobile equipment pro- It is a specic object of my invention to provided with electric control or communication l0 vide an electric relay which is inexpensive and facilities, or. both. The present-day tendency is simple to manufacture and which will render toward increased vehicle speeds and rates of acreliable service under extreme shoclr, vibration. celeration and deceleration, and as vehicle speeds and temperature, altitude, and humidity limits and accelerating rates are increased and more For a more complete understanding of my in closely. regulated, thecontrolequipment has Ibe-` 16 vention itself and a further appreciation of its exacting 'service' is'requlred of each ofthe comhad to the following detailed specification taken ponentelements. As the process of improvement in conjunction with the accompanying drawing tures of the older equipment and elements are 20 relayembodying my invention; Fig. 2 is a plan must be overcome by a new and improved design Fig 4 1s an exploded perspective View of certain in order to open the way for further overall detalls of the relay of Fiss 1 2, and 3, Fig s is development. 245 a. side elevation of an electric relay embodying The present invention then relates particularly my inventlon 1n a modlfed form Flg 6 1S a P1911 to electric relays foi use in connection with trans- VleW 0f the relay 0f Flg 5, and Fig 7 1s a fragu which may be subjected'either simultaneously or the relay illustrated at Figs' ands' consecutively to relatively large impact and vi- Referrmg now to the drawmg and parmcularly bratory forces and to large and relatively pert0 Figs' 1 to 4 ncluslvef my relay comprises a' vehicle speeds or rapid changes in the direction frame '01S mpumed up@ a base Hang provid?? of vehicle motion. My relay is also designed to Centrally 0f.1ts blght with a' magnetlc core render dependable service under extreme condi-y attached at lts base to the frame and extendmg tions of temperature altitude and humidity in parallel spaced relation with the legs of the Accordingly it is ageneral object of my New frame, The upper end of the core I2 serves pivotally to support a rockable magnetic armature um) to provlde a new and-1mproved electr 1c relay 40 I3 in such a position that one end of the armature the frame.

Any desired arrangement of stationary contact structure may be mounted upon one or both of the outside legs of the magnetic frame I 0. At

by facilitating adaptation and incorporationlof manner regardless of the imposition thereon of insulating compound. The supporting blocks I4 considerable external force. and I5 are attached to 'the 'It is a. further object of my invention to provide the frame I0 by any suitable, connecting means a new and improved electric relay'designed to such as rivets I6 and serve to support a plurality permit mounting in any position and to withstand of stationary contact members I1. Suitable movwithout substantial eiect upon its operation relaing contact members I8 are mounted upon the upon the core cal strength even at at substantially varmature I3 loosely movable armature I3 and insulated therefrom. In the form of the invention shown at Figs. 1, 2,

and 3,*the movable contacts I3 are mounted at opposite .ends of electrically conducting contact spring vstrips I9 which extend 'in' parallel spaced 1 relation to the armature I3 and are attached to the ends of a pair of transverse insulating members 2B mounted upon the armature I3. It will lbe noted that the contactsII and I8 are arranged with two pairs normally open and two pairs normally closed. Either of these two pairs-,may to advantage be connected in series circuit relation, since, 4especially at high altitudes, it has lbeen breaks in series is more efficacious than a single the same total gap'. In order to establish an actuating magnetic flux through a circuit comprising the long leg of the vframe. I, the Vcore'IZ and the armature I3, I provide an energizing coil or winding 2I positioned I2 between the legs of the U,shaped For vture for long periods the winding 2l may be wrapped upon a spool2la formed of a phenolic condensation product and coated with cellulose acetate. rllfhe phenolic product provides mechanihigh temperatures and the acetate is non-corrosive.

For the purposeof minimizing the effect oi external'forees which might be imposed upon vthe relay, the armature I3 is rockablymounted of a new and improved; knife-edge bearing. Re-

Figs.'3 and 4, the

ferring now particularly to its center of gravity by means the purpose of withstanding moisrelay core I0 component parts 3B to a position spaced from the The fiat leaf spring 33 is preferably relatively stiff and has a high natural period of vibration, thereby leaf spring invention, the resonant frequency of all stationferent value than that of the armature. Such an arrangement, in combination with my improved amature suspension gives .a'maximum reliability in severe high frequency vibration, such as is present in aircraft.

At Figs. 5, 6, and '7, I have form of my relay which is somewhat `similar to that shown at Figs. .1 to 4, inclusive, and the corresponding of which have been assigned like reference numerals. A few minor variations in the general arrangement have been shown for illustrative purposes. In the first place, the base II is made of insulating material so that a stationary contact post 40 and associated terminal shown a modified i connector 4I may be mounted directly upon the mentfof the armature I3. To vprovide an -abutknife-edge bearing comprises a substantially Il-shaped saddle 30 having a substantially flat -apertured-bight portion and rigidly attached to the upper end of the core I2 by means of a ,bolt 3I. The saddle 30 is provided for at least a portion of its width with a transverse ridge 32'which serves as a knife-edge supportfor the armature I3. As shown inl the drawing, the armature I3 may, if desiredy have a as at 33, to provide .a knife-edge seat for cooperation with the ridge 32, It will be evident that when the armature I3 is positioned within the saddle 30, the upturned en d portions of the shallowtransverse groove,

ufshaped saddle serve to restrain any lateral or pose of firmly connecting the U-shaped saddle 30 to the end of the' core ing the amature I2 and loosely retain- I3 within the saddle. As will be evident, particularly from an examination of Fig. 3, the body'portion ofthe double shouldered washer 34 is of greater diameter than thebolt receiving aperture in the saddle 3G so that when the bolt 3| is screwed downtightly into the core I2, the lower surface of the washer 34 holds-the saddle 30 firmly in engagement with the core. The upper overhanging annular shoulder of the washer 34 is spaced from the lower surface of the wast.` er by a distance greater than the thickness of the armature I3 so that. while 4the upper shoulder of the jwasher 34 serves to hold the within the saddle 30, it does permit rocking movement of the armature under the influence of a biasing spring andthe magnetic attractive force betweenthe larmature and the long leg of the relay frame. A lock washer 35 may alsobe provided to prevent loosening of .the bolt 3i. .as the' result of continued vibration. The, armature to provide integrally therewith a pair ment for the xed end of the at biasing spring 36, a nonmagnetic metallic support 43 is attached to the short leg of the magnetic frame II). Also,

4according to this modification a longitudinally split movable bridging trically connected to the armature I3. The purcontact spring 4,4 is elecpose of the split contact is to keep the contact resistance at a minimum.'

Referring now particularly it 4will be noted that, as in the previously described modif'lcation, the armature I3 is loosely mounted within a U-shaped saddle the saddle and armature are retained in posi- 45 differs from the 4 in that its head portion is formed of spaced those provided by the bolt 3| of Fig.

annular shoulders such as washer 34 of Fig. bolt 45 is screwed down firmly of the'saddle 30 in order rigidly to attach-the saddle to the end of the-core I2, annular shoulder ofthe bolt 45 merely overhangs a bolt receiving aperture 46 in the armature I3 and serves to prevent upward displacement of the armature and unseating thereof with respect to the saddle 30. It will be understood that the distance betweenthe annular -shoulders on the head 'of the bolt 30 is greater than the thickness of the armature I3 so that'the armature is only loosely held within the saddle. From Fig. 6 itwill also be noted that the bolt receiving aperture 45 in the armature I3 may be elongated to a somewhat noncircular form so that sive, rests at substantially further to protect the relay .against external vibratory forces. .Furthermore, in order to realize the fullest advantages of my the general arrangement' of the relay of Figa 5 and 6 is not to Figs. 6 and '1,

30 and both asaisa ture to a position spaced from said frame.

2. In an electromagnetic relay subject to large unidirectional and oscillatory accelerating forces,

' a stationary magnetic frame, a magnetic armature pivotally mountedfor movement toward and frame, means for mounting said armature comprising a substantially U-shaped saddle having a transverse bight portion providedV internally with a transverse ridge,- said celerating forces,

of appreciable anced thereby tn render the movement of said armature substantially independent ofA said acmeans for mounting said armaa substantially U-shaped saddle ture comprising said frame portion.

4. In an electric relay subject to large uniectional and oscillatory accelerating forces, a stationary magnetic frame including a coil core. a` substantially U-shaped saddle, of appreciable means for ixedly member to said core and 

